The invention relates to novel heteroaryl derivatives to their preparation and to their use as medicaments, in particular for treating tumors.
According to one aspect of the present invention, novel pyridine derivatives are provided of formula 1
wherein
R, R1, R2, R3 can be attached to any of the pyridine carbon atoms C2-6, and are the same or different and independently of one another are hydrogen, hydroxyl straight-chain or branched C1-8 alkyl, C3-7 cycloalkyl, straight-chain or branched C1-8 alkylcarbonyl, suitably acetyl, straight-chain or branched C1-8 alkoxy, halogen, aryl-C1-8 alkoxy, suitably benzyloxy or phenylethyloxy, nitro, amino, mono-C1-4 alkylamino, di-C1-4 alkylamino, C1-8 alkoxycarbonylamino, C1-6 alkoxycarbonylamino-C1-8 alkyl, cyano, straight-chain or branched cyano-C1-6 alkyl, carboxyl, C1-8 alkoxycarbonyl, C1-4 alkyl which is substituted by one or more fluorine atoms, suitably the trifluoromethyl group, carboxy-C1-8 alkyl or C1-8 alkoxycarbonyl-C1-6 alkyl C2-6 alkenyl, suitably allyl, C2-6 alkynyl, suitably ethynyl or propargyl, straight-chain or branched cyano-C1-6 alkyl, suitably cyanomethyl, aryl, where the aryl radical may be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of halogen, straight-chain or branched C1-8 alkyl, C3-7 cycloalkyl, carboxyl, straight-chain or branched C1-8 alkoxycarbonyl, suitably tert-butoxycarbonyl, by trifluoromethyl, hydroxyl, straight-chain or branched C1-8 alkoxy, suitably methoxy or ethoxy, benzyloxy, nitro, amino, mono-C1-4 alkylamino, di-C1-4 alkylamino, cyano, straight-chain or branched cyano-C1-6 alkyl, where additionally R and R1 and/or R2 and R3 may form a fused aromatic 6-membered ring with the pyridine ring forming a quinoline or acridine ring which can be substituted at any C atom ring position by the radicals R, R1, R2 and R3 having the meanings mentioned above;
Z is oxygen or sulfur, where the radical 
xe2x80x83substituted on the pyridine heterocycle can be attached to C atoms C2-C6 of the pyridine ring;
P, Q are independently of one another oxygen or in each case two hydrogen atoms as in xe2x80x94CH2xe2x80x94;
X is nitrogen or C-R5, where R5 is hydrogen or C1-6 alkyl;
n,m are independently of one another a cardinal number between 0 and 3, with the proviso that in the case when n is 0, X is a CR5R6 group where R5 and R6 are independently of one another hydrogen or C1-6 alkyl and that the nitrogen atom adjacent to the Cxe2x95x90Z group is substituted by a hydrogen atom or a C1-6 alkyl group;
R4 a straight-chain or branched C1-20 alkyl radical which can be saturated or unsaturated, with one to three double and/or triple bonds, and which can be unsubstituted or can be substituted at the same or different C atoms by one, two or more aryl, heteroaryl, halogen, C1-6 alkoxy, amino, mono-C1-4 alkylamino, cyano, xe2x80x94Cxe2x95x90NH (NH2), or di-C1-4 alkylamino; a C6-14 aryl radical, carboxy, C1-4 alkoxycarbonyl, C6-14 aryl-C1-4 alkyl radical or a C2-10 heteroaryl or C2-10 heteroaryl-C1-4 alkyl radical which contains one or more heteroatoms of N, O or S, where the C1-4 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and where the C6-14 aryl or C2-10 heteroaryl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of straight-chain or branched C1-8 alkyl, C3-7 cycloalkyl, halogen, cyano, C1-6 alkoxycarbonylamino, C1-4 alkoxy, carboxyl, C1-8 alkoxycarbonyl, straight-chain or branched C1-4 alkyl which is substituted by one or more fluorine atoms, suitably trifluoromethyl, hydroxyl, straight-chain or branched C1-8 alkoxy, suitably methoxy or ethoxy, where adjacent oxygen atoms can also be linked by C1-2 alkylene groups, suitably by a methylene group, benzyloxy, nitro, amino, mono-C1-4 alkylamino, di-C1-4 alkylamino, aryl, which for its part can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of straight-chain or branched C1-8 alkyl, C3-7 cycloalkyl, carboxyl, straight-chain or branched C1-8 alkoxycarbonyl, trifluoromethyl, hydroxyl, straight-chain or branched C1-8 alkoxy, suitably methoxy or ethoxy, benzyloxy, nitro, amino, mono-C1-4 alkylamino, di-C1-4 alkylamino, cyano, straight-chain or branched cyano-C1-6 alkyl;
and their structural isomers and stereoisomers, particularly tautomers, diastereomers and enantiomers, and their pharmaceutically acceptable salts, particularly acid addition salts, are provided.
Thus, for example, the compounds of formula (1) according to the present invention which have one or more centers of chirality and which are present as racemates can be separated by methods known per se into their optical isomers, i.e. enantiomers or diastereomers. The separation can be carried out by column separation on chiral phases or by recrystallization from an optically active solvent or using an optically active acid or base or by derivatization with an optically active reagent, such as, for example, an optically active alcohol, and subsequent removal of the radical.
Furthermore, the pyridine derivatives of formula (1) of the present invention can be converted into their salts with inorganic or organic acids, in particular, for pharmaceutical use, into their pharmaceutically acceptable salts. Acids which are suitable for this purpose include hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, fumaric acid, succinic acid, lactic acid, citric acid, acetic acid, tartaric acid, malic acid, embonic acid, malonic acid, trifluoroacetic acid or maleic acid.
Moreover, the compounds of formula (1) of the present invention can, if they contain a sufficiently acidic group, such as a carboxyl group, be converted into their salts with inorganic or organic bases, particularly for pharmaceutical use, into their pharmaceutically acceptable salts. Bases which are suitable for this purpose include sodium hydroxide, potassium hydroxide, calcium hydroxide, lysine, cyclohexylamine, ethanolamine, diethanolamine and triethanolamine.
According to a suitable embodiment, pyridine derivatives of formula 1 are provided in which R, R1, R2, R3, X, Z, P, Q, n and m have the meanings given above
Y is a substituent group of the same or different substituents of C1-6 alkyl, halogen, nitro, amino, mono-C1-6 alkylamino, di-C1-6 alkylamino, hydroxyl, C1-6 alkoxy, benzyloxy, carboxyl, C1-6 alkoxycarbonyl, C1-6 alkoxycarbonylamino, C1-6 alkyl mono- or polysubstituted with fluorine, suitably trifluoromethyl, C6-10 aryl, and C6-10 aryl-C1-6 alkyl, and
R4 is a straight-chain or branched C1-20 alkyl radical which can be saturated or unsaturated, with one to three double and/or triple bonds, and which can be unsubstituted or substituted on the same or different C atoms by one, two or more aryl, heteroaryl, halogen, C1-6 alkoxy, amino, mono-C1-4 alkylamino or di-C1-4 alkylamino;
a phenyl ring or a naphthyl ring, each of which can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of straight-chain or branched C1-8 alkyl, C3-7 cycloalkyl, halogen, cyano, C1-6 alkoxycarbonylamino, C1-6 alkoxy, carboxyl, C1-8 alkoxycarbonyl, straight-chain or branched C1-6 alkyl which is substituted by one or more fluorine atoms, suitably trifluoromethyl, hydroxyl, straight-chain or branched C1-8 alkoxy, suitably methoxy or ethoxy, where adjacent oxygen atoms can also be linked by C1-2 alkylene groups, suitably a methylene group, benzyloxy, nitro, amino, mono-C1-4 alkylamino, di-C1-4 alkylamino, aryl, which can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of straight-chain or branched C1-8 alkyl, C3-7 cycloalkyl, carboxyl, straight-chain or branched C1-8 alkoxycarbonyl, trifluoromethyl, hydroxyl, straight-chain or branched C1-8 alkoxy, suitably methoxy or ethoxy, benzyloxy, nitro, amino, mono-C1-4 alkylamino, di-C1-4 alkylamino, cyano, straight-chain or branched cyano-C1-6 alkyl;
a 2-, 4-, 5- or 6-pyrimidinyl radical, or a 2-, 4-, 5- or 6-pyrimidinyl -C1-4 alkyl radical, wherein the C1-4 alkyl radical can be unsubstituted or mono- or polysubstituted by identidal or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2-, 4-, 5- or 6-pyrimidinyl radical can be unsubstituted or mono- to trisubstituted by the same or different substituents from the group of hydrogen, or Y;
a 3-, 4-, 5- or 6-pyridazinyl radical, or a 3-, 4-, 5- or 6-pyridazinyl-C1-4 alkyl radical, wherein the C1-4 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 3-, 4-, 5- or 6-pyridazinyl radical can be unsubstituted or mono- or up to trisubstituted by the same or different substituents from the group of hydrogen, or Y;
a 2-, 3-, 5- or 6-pyrazinyl radical, or a 2-, 3-, 5- or 6-pyrazinyl-C1-4 alkyl radical, wherein the C1-4 alkyl radical can be unsubstituted or mono- or polysubstituted by identidal or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2-, 3-, 5- or 6-pyrazinyl radical can be unsubstituted or mono- to trisubstituted by the same or different substituents from the group of hydrogen, or Y;
a 3-, 4-, 5-, 6-, 7-, or 8-cinnolinyl radical, or a 3-, 4-, 5-, 6-, 7-, or 8-cinnolinyl-C1-4 alkyl radical, wherein the C1-4 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 3-, 4-, 5-, 6-, 7-, or 8-cinnolinyl radical can be unsubstituted or mono- or up to pentasubstituted by the same or different substituents from the group of hydrogen, or Y;
a 2-, 4-, 5-, 6-, 7-, or 8-quinazolinyl radical, or a 2-, 4-, 5-, 6-, 7-, or 8-quinazolinyl-C1-4 alkyl radical, wherein the C1-4 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of hydrogen, C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2-, 4-, 5-, 6-, 7-, or 8-quinazolinyl radical can be unsubstituted or mono- or up to pentasubstituted by the same or different substituents from the group of hydrogen, or Y;
a 2-, 3-, 5-, 6-, 7-, or 8-quinoxalinyl radical, or a 2-, 3-, 5-, 6-, 7-, or 8-quinoxalinyl-C1-4 alkyl radical, wherein the C1-4 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2-, 3-, 5-, 6-, 7-, or 8-quinoxalinyl radical can be unsubstituted or mono- or up to pentasubstituted by the same or different substituents from the group of hydrogen, or Y;
a 1-, 4-, 5-, 6-, 7-, or 8-phthalazinyl radical, or a 1-, 4-, 5-, 6-, 7-, or 8-phthalazinyl-C1-4 alkyl radical, wherein the C1-4 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 1-, 4-, 5-, 6-, 7-, or 8-phthalazinyl radical can be unsubstituted or mono- to pentasubstituted by the same or different substituents from the group of hydrogen, or Y;
a 2-, 3-, 4-, 5-, 6-, 7- or 8-quinolyl radical, or a 2-, 3-, 4-, 5-, 6-, 7 or 8-quinolyl-C1-4 alkyl radical, wherein the C1-4 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2-, 3-, 4-, 5-, 6-, 7- or 8-quinolyl radical can be unsubstituted or mono- or up to hexasubstituted by the same or different substituents from the group of hydrogen, or Y;
a 1-, 3-, 4-, 5-, 6-, 7- or 8-isoquinolyl radical, or a 1-, 3-, 4-, 5-, 6-, 7-or 8-isoquinolyl-C1-4 alkyl radical, wherein the C1-4 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 1-, 3-, 4-, 5-, 6-, 7- or 8-isoquinolyl radical can be unsubstituted or mono- or up to hexasubstituted by the same or different substituents from the group of hydrogen, or Y;
a 2-, 6-, 8- or 9-[9H]-purinyl radical, or a 2-, 6-, 8- or 9-[9H]-purinyl-C1-4 alkyl radical, wherein the C1-4 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2-, 6-, 8- or 9-[9H]-purinyl radical can be unsubstituted or mono- to trisubstituted by the same or different substituents from the group of hydrogen, or Y;
a 2-, 6-, 7- or 8-[7H]-purinyl radical, or a 2-, 6-, 7- or 8-[7H]-purinyl-C1-4 alkyl radical, wherein the C1-4 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2-, 6-, 7- or 8-[7H]-purinyl radical can be unsubstituted or mono- or up to trisubstituted by the same or different substituents from the group of hydrogen, or Y;
a 1-, 2-, 3-, 4-, 5-, 6-, 7-, 8- or 9-acridinyl radical, or a 1-, 2-, 3-, 4-, 5-, 6-, 7-, 8-or 9-acridinyl-C1-4 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 1-, 2-, 3-, 4-, 5-, 6-, 7-, 8- or 9-acridinyl radical can be unsubstituted or mono- or up to octasubstituted by the same or different substituents from the group of hydrogen, or Y;
a 1-, 2-, 3-, 4-, 5-, 6-, 7-, 8- or 9-phenanthridinyl radical, or a 1-, 2-, 3-, 4-, 5-, 6-, 7-, 8- or 9-phenanthridinyl-C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of hydrogen, C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 1-, 2-, 3-, 4-, 5-, 6-, 7-, 8- or 9-phenanthridinyl radical can be unsubstituted or mono- or up to octasubstituted by Y;
a 2-, 3-, 4-, 5- or 6-pyridyl radical, which can be unsubstituted or mono- or up to tetrasubstituted by Y;
a 2-, 3-, 4-, 5- or 6-pyridinyl-C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2-, 3-, 4-, 5- or 6-pyridinyl radical can be unsubstituted or mono- or up to tetrasubstituted by the same or different substituents from the group of hydrogen, or Y;
a 2-, 3-, 4- or 5-thienyl radical, or a 2-, 3-, 4- or 5-thienyl-C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2-, 3-, 4- or 5-thienyl radical can be unsubstituted or mono- to trisubstituted by the same or different substituents from the group of hydrogen, or Y;
a 2-, 4-, or 5-thiazolyl radical, or a 2-, 4-, or 5-thiazolyl-C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2-, 4-, or 5-thiazolyl radical can be unsubstituted or mono- or disubstituted by the same or different substituents from the group of hydrogen, or Y;
a 3-, 4-, or 5-isothiazolyl radical, or a 3-, 4-, or 5-isothiazolyl-C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 3-, 4-, or 5-isothiazolyl radical can be unsubstituted or mono- or disubstituted by the same or different substituents from the group of hydrogen, or Y;
a 2-, 4-, 5-, 6-, or 7-benzothiazolyl radical, or a 2-, 4-, 5-, 6-, or 7-benzothiazolyl-C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2-, 4-, 5-, 6-, or 7-benzothiazolyl radical can be unsubstituted or mono- to tetrasubstituted by the same or different substituents from the group of hydrogen, or Y;
a 1-, 2-, 4-, or 5-imidazolyl radical, or a 1-, 2-, 4-, or 5-imidazolyl-C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 1-, 2-, 4-, or 5-imidazolyl radical can be unsubstituted or mono- or up to trisubstituted by the same or different substituents from the group of hydrogen, or Y;
a 1-, 3-, 4-, or 5-pyrazolyl radical, or a 1-, 3-, 4- or 5-pyrazolyl-C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 1-, 3-, 4- or 5-pyrazolyl radical can be unsubstituted or mono- or up to trisubstituted by the same or different substituents from the group of hydrogen, or Y;
a 1-, 2-, 3-, 4-, or 5-pyrrolyl radical, or a 1-, 2-, 3-, 4-, or 5-pyrrolyl-C1-6 -alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 1-, 2-, 3-, 4- or 5-pyrrolyl radical can be unsubstituted or mono- to tetrasubstituted by the same or different substituents from the group of hydrogen, or Y;
a 1-, 3-, or 5-[1.2.4]-triazolyl radical, or a 1-, 3-, or 5-[1.2.4]-triazolyl -C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of hydrogen, C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 1-, 3-, or 5-[1.2.4]-triazolyl radical can be unsubstituted or mono- or disubstituted by Y;
a 1-, 4-, or 5-[1.2.3]-triazolyl radical, or a 1-, 4-, or 5-[1.2.3]-triazolyl -C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 1-, 4-, or 5-[1.2.3]-triazolyl radical can be unsubstituted or mono- or disubstituted by the same or different substituents from the group of hydrogen, or Y;
a 1- or 5-[1H]-tetrazolyl radical, or a 1-, or 5-[1H]-tetrazolyl-(C1-C6)-alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 1-, or 5-[1H]-tetrazolyl radical can be unsubstituted or substituted by hydrogen, or Y;
a 2- or 5-[2H]-tetrazoyl radical, or a 2- or 5-[2H]-tetrazolyl-C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2- or 5-[2H]-tetrazolyl radical can be unsubstituted or substituted by hydrogen, or Y;
a 2-, 4-, or 6-[1.3.5]-triazinyl radical, or a 2-, 4-, or 6-[1.3.5]-triazinyl -C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of hydrogen, or Y;
a 2-, 4-, or 5-oxazolyl radical, or a 2-, 4-, or 5-oxazolyl-C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 2-, 4-, or 5-oxazolyl radical can be unsubstituted or mono- or disubstituted by the same or different substituents from the group of hydrogen, or Y;
a 3-, 4-, or 5-isoxazolyl radical, or a 3-, 4-, or 5-isoxazolyl-C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 3-, 4-, or 5-isoxazolyl radical can be unsubstituted or mono- or disubstituted by the same or different substituents from the group of hydrogen, or Y;
a 1-, 2-, 3-, 4-, 5-, 6- or 7-indolyl radical, or a 1-, 2-, 3-, 4-, 5-, 6-, or 7-indolyl-C1-6 alkyl radical, wherein the C1-6 alkyl radical can be unsubstituted or mono- or polysubstituted by the same or different substituents from the group of C1-6 alkyl, halogen or oxo (xe2x95x90O),, and the 1-, 2-, 3-, 4-, 5-, 6- or 7-indolyl radical can be unsubstituted or mono- to hexasubstituted by the same or different substituents from the group of hydrogen, or Y, and the isomers, in particular tautomers, diastereomers and enantiomers, and the pharmaceutically acceptable salts, particularly acid addition salts thereof.
According to a further embodiment of the present invention, pyridine derivatives of formula (1) are provided in which R, R1, R2, R3, X, Z, P, Q, n and m have the meanings given above and R4 is phenyl which is unsubstituted or substituted by one to five the same or different C1-6 alkoxy groups, wherein adjacent oxygen atoms can also be linked by C1-2 alkylene groups.
According to a further embodiment of the present invention, pyridine derivatives of formula (1) are provided in which R4 has the meanings given above, R, R1, R2, R3 are each a hydrogen atom, Z is an oxygen atom, X is a nitrogen atom, P and Q each represent two hydrogen atoms as in xe2x80x94CH2xe2x80x94, m is zero and n is 2.
According to a further embodiment of the present invention, pyridine derivatives of formula (1) are provided in which R, R1, R2, R3, X, Z, P, Q, n and m have the meanings given above, and R4 is 3,5-dimethoxyphenyl.
According to yet a further embodiment of the present invention, pyridine derivatives of formula (1) are provided in which R, R1, R2, R3 are each a hydrogen atom, Z is an oxygen atom, X is a nitrogen atom, P and Q are each two hydrogen atoms as in xe2x80x94CH2xe2x80x94, m is zero, n is 2, and R4 is a 3,5-dimethoxyphenyl radical.
According to a further aspect of the present invention, a process is provided for preparing pyridine derivatives of formula (1), by reacting a pyridine carboxylic acid of formula (2) 
in which R, R1, R2, R3 have the meanings given above, Z is an oxygen or sulfur atom, and Y represents a leaving group such as halogen, hydroxyl, (C1-C6)-alkoxy, such as methoxy or ethoxy, xe2x80x94O-tosyl, xe2x80x94O-mesyl or imidazolyl, with an amine of formula (3) 
in which R4, X, P, Q, m and n are as defined above, and optionally using diluents and auxiliaries.
Synthesis Route
The compounds of formula 1 can be obtained according to the following reaction scheme 1: 
The starting materials of formulae (2) and (3) are either commercially available or can be prepared by procedures known per se. The starting materials of formulae (2) and (3) are useful intermediates for preparing the pyridine derivatives of formula (1) of the present invention.
The solvents and auxiliaries to be optionally used, and the reaction parameters to be used, such as reaction temperature and reaction time, are known from the literature or are familiar to the person skilled in the art owing to his expert knowledge.
The pyridine derivatives of formula (1) of the present invention are suitable as medicaments, particularly as antitumor agents, for treating mammals, particularly man, and also domestic animals such as horses, cattle, dogs, cats, rabbits, sheep, poultry and the like.
According to a further aspect of the invention, a therapeutic method is provided for controlling tumors in mammals, particularly man, by administering at least one pyridine derivative of formula (1) to a mammal in an amount effective for the treatment of the tumor. The therapeutically effective dose of the pyridine derivative according to the invention which is to be administered for the treatment depends inter alia on the nature and the stage of the oncosis, the age and the sex of the patient, the type of administration and the duration of the treatment and can be determined by routine dosage ranging. Administration can take place orally, rectally, buccally (for example sublingually), parenterally (for example subcutaneously, intramuscularly, intradermally or intravenously), topically or transdermally.
According to a further aspect of the prinvention, medicaments are provided for the treatment of tumors, comprising as active ingredient, at least one pyridine derivative of formulae (1) or a pharmaceutically acceptable salt thereof, optionally together with conventional pharmaceutically acceptable auxiliaries, additives and carriers. These can be solid, semisolid, liquid or aerosol preparations. Suitable solid preparations are, for example, capsules, powders, granules, tablets. Suitable semisolid preparations are, for example, ointments, creams, gels, pastes, suspensions, oil-in-water and water-in-oil emulsions. Suitable liquid preparations are, for example, sterile aqueous preparations for parenteral administration which are isotonic with the blood of the patient.